System and apparatus for treating a tissue site having an in-line canister

ABSTRACT

A canister for use in administering reduced pressure to a tissue site includes a center body, a first end cap, and a second end cap. The center body includes a first end, second end, and a number of fluidly separate body conduits. The first end cap is connected to the first end of the center body and includes a number of return conduits fluidly connecting one body conduit to another. The first end has a port for receiving a conduit in fluid communication with the tissue site. The second end cap is connected to the second end of the center body and includes a number of return conduits fluidly connecting one body conduit to another. The second end cap has a port for receiving a conduit in fluid communication with a reduced pressure source. The fluid connection between the body conduits and the return conduits creates a continuous, tortuous pathway.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/653,997, filed Oct. 17, 2012, which claims priority to U.S.Provisional Patent Application No. 61/548,129, filed Oct. 17, 2011,entitled “SYSTEM AND APPARATUS FOR TREATING A TISSUE SITE HAVING ANIN-LINE CANISTER,” all of which are hereby incorporated by reference intheir entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates generally to reduced pressure treatmentsystems and more particularly to a system and apparatus for treating atissue site having an in-line canister.

Description of Related Art

Clinical studies and practice have shown that providing a reducedpressure in proximity to a tissue site augments and accelerates thegrowth of new tissue at the tissue site. The applications of thisphenomenon are numerous, but one particular application of reducedpressure involves treating wounds. This treatment (frequently referredto in the medical community as “negative pressure wound therapy,”“reduced pressure therapy,” or “vacuum therapy”) provides a number ofbenefits, including migration of epithelial and subcutaneous tissues,improved blood flow, and micro-deformation of tissue at the wound site.Together these benefits result in increased development of granulationtissue and faster healing times. Typically, reduced pressure is appliedby a reduced pressure source to tissue through a porous pad or othermanifold device. The porous pad contains cells or pores that are capableof distributing reduced pressure to the tissue and channeling fluidsthat are drawn from the tissue. The porous pad often is incorporatedinto a dressing having other components that facilitate treatment.

SUMMARY

The problems presented by existing reduced pressure treatment systemsare solved by the systems and methods of the illustrative embodimentsdescribed herein. In one illustrative embodiment, a canister for use inadministering reduced pressure to a tissue site includes a center body,a first end cap, and a second end cap. The center body has a first end,a second end, and a number of fluidly separate body conduits extendingfrom the first end to the second end. The first end cap is connected tothe first end of the center body and has a number of return conduitsconfigured to fluidly connect one of the body conduits with another ofthe body conduits. The first end cap further has a port for receiving aconduit in fluid communication with the tissue site. The second end capis connected to the second end of the center body and has a number ofreturn conduits configured to fluidly connect one of the body conduitswith another of the body conduits. The second end cap further has a portfor receiving a conduit in fluid communication with a reduced pressuresource. The fluid connection between the body conduits and the returnconduits of the first and second end caps creates a continuous, tortuouspathway.

In another illustrative embodiment, a canister for use in administeringreduced pressure to a tissue site includes a center body, a first endcap and a second end cap. The center body has a first end, a second end,and a number of fluidly separate body conduits extending from the firstend to the second end. An absorbent material is positioned in each ofthe number of fluidly separate body conduits. The first end cap isconnected to the first end of the center body, and the first end cap hasan inlet port, an outlet port, and a first plenum for receiving fluids.The second end cap is connected to the second end of the center body andhas a second plenum for receiving fluids.

In yet another illustrative embodiment, a system for use inadministering reduced pressure to a tissue site includes areduced-pressure dressing, an in-line canister, and a reduced-pressuretreatment unit. The reduced-pressure dressing is positioned proximatethe tissue site and includes a manifold positioned within the tissuesite for delivering reduced pressure to the tissue site. The in-linecanister is fluidly connected to the reduced-pressure dressing through afirst conduit and is operable to receive and store fluid received fromthe tissue site. The in-line canister includes a center body, a firstend cap, and a second end cap. The center body has a first end, a secondend, and a number of fluidly separate body conduits extending from thefirst end to the second end. The first end cap is connected to the firstend of the center body and has a number of return conduits configured tofluidly connect one of the body conduits with another of the bodyconduits. The first end cap further has a port for receiving a conduitin fluid communication with the tissue site. The second end cap isconnected to the second end of the center body and has a number ofreturn conduits configured to fluidly connect one of the body conduitswith another of the body conduits. The second end cap further has a portfor receiving a conduit in fluid communication with a reduced pressuresource. The fluid connection between the body conduits and the returnconduits of the first and second end caps creates a continuous, tortuouspathway. The reduced-pressure treatment unit is fluidly connected to thecanister through a second conduit and includes a reduced pressure sourcefor providing reduced pressure to the tissue site.

Other objects, features, and advantages of the illustrative embodimentswill become apparent with reference to the drawings and detaileddescription that follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view, with a portion shown in crosssection, of an illustrative embodiment of a system for treating a tissuewith reduced pressure;

FIG. 2 illustrates a side view of an illustrative embodiment of acanister for use in the system shown in FIG. 1;

FIG. 3 illustrates a front view of a first end cap of the canister shownin FIG. 2 taken along line 3-3;

FIG. 4 illustrates a back view of a second end cap of the canister shownin FIG. 2 taken along line 4-4;

FIG. 5 illustrates a cross-sectional view of the center body of thecanister shown in FIG. 2 taken along line 5-5;

FIG. 6 illustrates a cross-sectional side view of the canister of FIG.2;

FIG. 7 illustrates a side view of another illustrative embodiment of acanister for use in the system shown in FIG. 1;

FIG. 8 illustrates an exploded side view of the canister shown in FIG.7;

FIG. 9 illustrates a front view of a first end cap of the canister shownin FIG. 7 taken along line 9-9;

FIG. 10 illustrates a back view of a second end cap of the canistershown in FIG. 7 taken along line 10-10;

FIG. 11 illustrates a cross-sectional side view of the canister shown inFIG. 7;

FIGS. 12A and 12B illustrate a perspective view of another illustrativeembodiment of a canister for use in the system shown in FIG. 1; and

FIGS. 13A and 13B illustrate a perspective view of another illustrativeembodiment of a canister for use in the system shown in FIG. 1.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In the following detailed description of several illustrativeembodiments, reference is made to the accompanying drawings that form apart hereof, and in which is shown by way of illustration specificpreferred embodiments in which the invention may be practiced. Theseembodiments are described in sufficient detail to enable those skilledin the art to practice the invention, and it is understood that otherembodiments may be utilized and that logical structural, mechanical,electrical, and chemical changes may be made without departing from thespirit or scope of the invention. To avoid detail not necessary toenable those skilled in the art to practice the embodiments describedherein, the description may omit certain information known to thoseskilled in the art. The following detailed description is, therefore,not to be taken in a limiting sense, and the scope of the illustrativeembodiments are defined only by the appended claims. Unless otherwiseindicated, as used herein, “or” does not require mutual exclusivity.

The term “reduced pressure” as used herein generally refers to apressure less than the ambient pressure at a tissue site that is beingsubjected to treatment. In most cases, this reduced pressure will beless than the atmospheric pressure at which the patient is located.Alternatively, the reduced pressure may be less than a hydrostaticpressure associated with tissue at the tissue site. Although the terms“vacuum” and “negative pressure” may be used to describe the pressureapplied to the tissue site, the actual pressure reduction applied to thetissue site may be significantly less than the pressure reductionnormally associated with a complete vacuum. Reduced pressure mayinitially generate fluid flow in the area of the tissue site. As thehydrostatic pressure around the tissue site approaches the desiredreduced pressure, the flow may subside, and the reduced pressure is thenmaintained. Unless otherwise indicated, values of pressure stated hereinare gauge pressures. Similarly, references to increases in reducedpressure typically refer to a decrease in absolute pressure, whiledecreases in reduced pressure typically refer to an increase in absolutepressure.

Referring to FIG. 1, an illustrative embodiment of a system 100 fortreating a tissue site 102 on a patient 104 with reduced pressure ispresented. The system 100 includes a reduced-pressure dressing 106 fordisposing proximate the tissue site 102 and a reduced-pressure treatmentunit 108 fluidly connected to the reduced-pressure dressing 106 forapplying reduced pressure to the tissue site 102. The system 100 furtherincludes a canister 110 fluidly connected to both the reduced-pressuredressing 106 and the reduced-pressure treatment unit 108. A firstconduit 112 connects the reduced-pressure dressing 106 to the canister110, and a second conduit 114 connects the reduced-pressure treatmentunit 108 to the canister 110. The canister 110 is operable to receiveand store fluids, including exudate, received from the tissue site 102.The canister 110 is configured to create a tortuous flow path for anyfluids received from the tissue site 102. There are several potentialadvantages to having an in-line canister positioned between a tube setand configured to create a tortuous flow path. For example, theconfiguration may allow for a smaller and more discrete vacuum deviceand more efficient absorption of the wound exudates. The volumetric sizeof the canister may be increased with virtually no impact to the size ofthe vacuum device.

The system 100 may be used with various types of tissue sites 102. Asused herein, the term “tissue site” may refer to a wound, such as awound 116, or defect located on or within any tissue, including but notlimited to, bone tissue, adipose tissue, muscle tissue, neural tissue,dermal tissue, vascular tissue, connective tissue, cartilage, tendons,or ligaments. The term “tissue site” may further refer to areas of anytissue that are not necessarily wounded or defective, but are insteadareas in which it is desired to add or promote the growth of additionaltissue. For example, reduced pressure tissue treatment may be used incertain tissue areas to grow additional tissue that may be harvested andtransplanted to another tissue location. The wound 116 may be through anepidermis 118 and into a subcutaneous tissue or any other tissue.Treatment of the tissue site 102 may include removal of fluids, e.g.exudate or ascites.

The reduced-pressure dressing 106 may include a manifold 120 positionedproximate the tissue site 102. The manifold 120 typically includes aplurality of flow channels or pathways that distribute fluids providedto and removed from the tissue site 102 around the manifold 120. In oneillustrative embodiment, the flow channels or pathways areinterconnected to improve distribution of fluids provided or removedfrom the tissue site 102. The manifold 120 may be a biocompatiblematerial that is capable of being placed in contact with the tissue site102 and distributing reduced pressure to the tissue site 102. Examplesof the manifold 120 may include, without limitation, devices that havestructural elements arranged to form flow channels, such as, forexample, cellular foam, open-cell foam, porous tissue collections,liquids, gels, and foams that include, or cure to include, flowchannels. The manifold 120 may be porous and may be made from foam,gauze, felted mat, or any other material suited to a particularbiological application. In one embodiment, the manifold 120 is a porousfoam and includes a plurality of interconnected cells or pores that actas flow channels. The porous foam may be a polyurethane, open-cell,reticulated foam such as GranuFoam® material manufactured by KineticConcepts, Incorporated of San Antonio, Tex. In some situations, themanifold 120 may also be used to distribute fluids such as medications,antibacterials, growth factors, and various solutions to the tissue site102. Other layers may be included in or on the manifold 120, such asabsorptive materials, wicking materials, hydrophobic materials, andhydrophilic materials.

In one illustrative embodiment, the manifold 120 may be constructed frombioresorbable materials that do not have to be removed from a patient'sbody following use of the system 100. Suitable bioresorbable materialsmay include, without limitation, a polymeric blend of polylactic acid(PLA) and polyglycolic acid (PGA). The polymeric blend may also includewithout limitation polycarbonates, polyfumarates, and capralactones. Themanifold 120 may further serve as a scaffold for new cell-growth, or ascaffold material may be used in conjunction with the manifold 120 topromote cell-growth. A scaffold is a substance or structure used toenhance or promote the growth of cells or formation of tissue, such as athree-dimensional porous structure that provides a template for cellgrowth. Illustrative examples of scaffold materials include calciumphosphate, collagen, PLA/PGA, coral hydroxy apatites, carbonates, orprocessed allograft materials.

The reduced-pressure dressing 106 may further include a cover or drape122 positioned over the manifold 120 to secure the manifold 120 at thetissue site 102 and to create a sealed space 124 over the tissue site102. The drape 122 has a first side 126, and a second, tissue-facingside 128. The drape 122 may be any material that provides a fluid sealadequate to maintain reduced pressure at a desired site given theparticular reduced-pressure source or subsystem involved. The drape 122may, for example, be an impermeable or semi-permeable, elastomericmaterial.

An attachment device 130 may be used to hold the drape 122 against aportion of the patient's intact epidermis 118 or another layer, such asa gasket or additional sealing member. The attachment device 130 maytake numerous forms. For example, the attachment device 130 may be amedically acceptable adhesive or bonding agent, such as apressure-sensitive adhesive, that extends about a periphery or all ofthe drape 122. The attachment device 130 may also be a sealing ring orother device. The attachment device 130 is disposed on the second,tissue-facing side 128 of the drape 122. Before use, the attachmentdevice 130 may be covered by a release liner (not shown).

In another embodiment, a seal layer (not shown) such as, for example, ahydrogel or other material may be disposed between the drape 122 and theepidermis 118 to augment or substitute for the sealing properties of theattachment device 130. In one embodiment, the drape 122 and the bondingcharacteristics of the drape 122 provide sealing sufficient to preventleakage greater than 0.5 L/min at 125 mmHg reduced pressure.

The reduced-pressure dressing 106 may further include a reduced-pressureinterface 132 positioned adjacent to or coupled to the drape 122 toprovide fluid access to the manifold 120. Another attachment device (notshown) similar to the attachment device 130 may be used to hold thereduced-pressure interface 132 against the drape 122. The first conduit112, the canister 110, and the second conduit 114 fluidly couples thereduced-pressure treatment unit 108 and the reduced-pressure interface132. The reduced-pressure interface 132 allows the reduced pressure tobe delivered to the tissue site 102. While the amount and nature ofreduced pressure applied to a tissue site will typically vary accordingto the application, the reduced pressure will typically be between −5 mmHg (−667 Pa) and −500 mm Hg (−66.7 kPa) and more typically between −75mm Hg (−9.9 kPa) and −300 mm Hg (−39.9 kPa).

The first and second conduits 112, 114 may be single lumen conduits,multi-lumen conduits, or a combination of a single lumen and multi-lumenconduit. In the instance either or both the first and second conduits112, 114 are a multi-lumen conduit, one lumen may be a primary lumen andanother lumen may be a sensing lumen for sensing the level of reducedpressure being applied to the tissue site 102. Liquids or exudatescommunicated from the manifold 120 through the first conduit 112 areremoved from the first conduit 112 and retained within the canister 110.

The reduced-pressure treatment unit 108 includes a reduced-pressuresource 134, and may further include an instrumentation unit 136. In anillustrative embodiment, the reduced-pressure source 134 is anelectrically-driven vacuum pump. In another implementation, thereduced-pressure source 134 may instead be a manually-actuated ormanually-charged pump that does not require electrical power. Thereduced-pressure source 134 instead may be any other type of reducedpressure pump, or alternatively a wall suction port such as thoseavailable in hospitals and other medical facilities. Thereduced-pressure source 134 may be housed within or used in conjunctionwith the reduced-pressure treatment unit 108, which may also include theinstrumentation unit 136. The instrumentation unit 136 may includesensors, processing units, alarm indicators, memory, databases,software, display units, and user interfaces that further facilitate theapplication of reduced pressure treatment to the tissue site 102. In oneexample, pressure-detection sensors (not shown) may be disposed at ornear the reduced-pressure source 134. The pressure-detection sensors mayreceive pressure data from the reduced-pressure interface 132 via lumensin the conduits 112, 114 that are dedicated to delivering reducedpressure data to the pressure-detection sensors. The pressure-detectionsensors may communicate with a processing unit that monitors andcontrols the pressure that is delivered by the reduced-pressure source134.

Referring now primarily to FIGS. 2-6, the canister 110 shown in thesystem 100 of FIG. 1 is presented in more detail. The canister 110 maybe referred to as an in-line canister since the canister 110 ispositioned between the first and second conduits 112, 114 that fluidlyconnect the reduced-pressure dressing 106 and the reduced-pressuretreatment unit 108. The canister 110 includes a center body 138, a firstend cap 140, and a second end cap 142. The canister 110 is configured tocreate a continuous, tortuous flow path represented by arrows 157. Thecontinuous, tortuous flow path is a unidirectional flow path.

The center body 138 includes a first end 144 and a second, opposing end146. A number of fluidly separate body conduits 148 extend from thefirst end 144 to the second end 146. The number of fluidly separate bodyconduits 148 may be an uneven number. For example, the number of fluidlyseparate body conduits 148 may be 3, 5, 7, or more. As shown, the numberof fluidly separate body conduits 148 is seven. The number may depend onthe desired length of the continuous, tortuous flow path. In a specificexample, the center body 138 may have a width, W, of approximatelyseveral inches, and more specifically, approximately 3 inches in someembodiments. The center body 138 may also have a length, L, between thefirst end and the second end 144, 146 of several inches in someembodiments. In more particular embodiments, the length L isapproximately 6 inches. Each of the number of fluidly separate bodyconduits 148 may have a diameter, d, or a width that allows for anapproximate canister 110 volumetric size of 170 cc. For example, in someembodiments, the diameter d is approximately 0.375 inches. It should beunderstood however, the width, W, and length, L, of the center body 138,the number of body conduits 148 contained within the center body 138,and the diameter, d, or width of the body conduits 148 may be adjustedaccording to the desired volumetric size of the canister 110.

The center body 138 is shown as having an oblong shape with a first side150 and a second, opposing side 152 that is both substantially planarand substantially parallel. It should be understood that while thecenter body 138 is shown as having an oblong shape with two sides thatare substantially planar and parallel, the oblong shape is but oneillustrative embodiment. The center body 138 may take a number ofshapes. For example, the center body 138 may be rectangular, square, orcylindrical. A top 154 and a bottom 156 of the center body 138 may berounded. Each of the number of fluidly separate body conduits 148 may bebonded together to form the center body 138. In one embodiment, each ofthe number of fluidly separate body conduits 148 are bonded together ina single column. In another embodiment, the number of fluidly separatebody conduits 148 are arranged in one or more columns or rows. In yetanother embodiment, the center body 138 is a single extruded piece. Thecenter body 138 may be formed of silicone or polyurethane, for example.The center body 138 may be made of a flexible material to make thecenter body less noticeable and more comfortable if worn under clothing.

The center body 138 may include an absorbent material (not shown)positioned within one or more of the number of fluidly separate bodyconduits 148. The absorbent material may be one of a hydrophilic foam, ahydrophilic paper, a hydrophilic powder, or a sodium polyacrylatematerial.

The canister 110 further includes the first end cap 140. The first endcap 140 is connected to the first end 144 of the center body 138. Thefirst end cap 140 may be connected to the center body 138 by aconnecting means such as an adhesive bond or a weld bond. The connectingmeans creates a fluid seal between the first end cap 140 and the centerbody 138. The first end cap 140 may be formed as a single piece. Thefirst end cap 140 may further be formed of silicone.

The first end cap 140 has a number of return conduits 158 configured tofluidly connect one of the body conduits 148 with another of the bodyconduits 148. In one embodiment, the return conduits 158 connect two ofthe number of body conduits 148 that are adjacent. The return conduits158 may function as turnabouts that redirect fluid received from oneconduit into another conduit. The return conduits 158 may redirect fluidinto an opposite direction. The first end cap 140 may include a numberof protrusions (not shown) corresponding to the return conduits 158. Thenumber of protrusions would be insertable into the corresponding bodyconduits 148.

The first end cap 140 has a port 160 for receiving an inlet conduit,such as the first conduit 112, that is in fluid communication with thetissue site 102. The first conduit 112 may be connected to the port 160by a connecting means such as an adhesive bond or a weld bond. Theconnecting means creates a fluid seal between the first conduit 112 andthe port 160. The port 160 is aligned with a first body conduit 170 ofthe number of body conduits 148 to facilitate fluid communicationbetween the first conduit 112 and the first body conduit 170 of thenumber of body conduits 148.

The canister 110 further includes the second end cap 142. The second endcap 142 is connected to the second end 146 of the center body 138. Thesecond end cap 142 may be connected to the center body 138 by aconnecting means such as an adhesive bond or a weld bond. The connectingmeans creates a fluid seal between the second end cap 142 and the centerbody 138. The second end cap 142 may be formed as a single piece. Thesecond end cap 142 may further be formed of silicone.

The second end cap 142 has a number of return conduits 164 configured tofluidly connect one of the body conduits 148 with another of the bodyconduits 148. In one embodiment, the return conduits 164 connect two ofthe number of body conduits 148 that are adjacent. The return conduits164 may function as turnabouts that redirect fluid received from oneconduit into another conduit. The return conduits 164 may redirect fluidinto an opposite direction. The second end cap 142 may include a numberof protrusions (not shown) corresponding to the return conduits 164. Thenumber of protrusions would be insertable into the corresponding bodyconduits 148.

The second end cap 142 has a port 166 for receiving an outlet conduit,such as the second conduit 114, that is in fluid communication with thereduced-pressure treatment unit 108 and, in particular, thereduced-pressure source 134. The second conduit 114 may be connected tothe port 166 by a connecting means such as an adhesive bond or a weldbond. The connecting means creates a fluid seal between the secondconduit 114 and the port 166. The port 166 is aligned with an endconduit 194 of the number of body conduits 148 to facilitate fluidcommunication between the second conduit 114 and the end conduit 194 ofthe number of body conduits 148. A hydrophobic filter (not shown) may beplaced in the second end cap 142, adjacent the port 166, to preventexudates from exiting the canister 110.

In operation, reduced pressure is supplied to the tissue site 102 by thereduced-pressure treatment unit 108. The canister 110 is a part of thesystem 100 that communicates the reduced pressure from thereduced-pressure treatment unit 108 to the tissue site 102. Whileapplying reduced pressure to the tissue site 102, fluids, includingliquids and exudates, may be removed from the tissue site 102. Theliquids and exudates removed from the tissue site 102 are collected andstored in the canister 110. The fluid connection between the bodyconduits 148 and the return conduits 158, 164 of the first and secondend caps creates a continuous, tortuous flow path that is represented bythe arrows 157. The continuous, tortuous flow path represented by thearrows 157 is a unidirectional flow path beginning at the port 160 inthe first end cap 140 and ending at the port 166 in the second end cap142. The continuous, tortuous flow path passes through the each of thenumber of fluidly separate body conduits 148.

Referring now primarily to FIG. 6, but also with reference to FIGS. 2-5,the number of body conduits 148 as shown is seven. The fluids removedfrom the tissue site 102 enter the canister 110 through the port 160 inthe first end cap 140. The fluids are delivered through the port 160 andinto a first body conduit 170 of the number of body conduits 148. Thefluids may then flow through the first body conduit 170 to a firstreturn conduit 172, positioned in the second end cap 142, and into asecond body conduit 174. The fluid from the second body conduit 174 maythen flow into a second return conduit 176, positioned in the first endcap 140, and to a third body conduit 178. The fluid from the third bodyconduit 178 may then flow into a third return conduit 180, positioned inthe second end cap 142, and to a fourth body conduit 182. The fluid fromthe fourth body conduit 182 may then flow into a fourth return conduit184, positioned in the first end cap 140, and to a fifth body conduit186. The fluid from the fifth body conduit 186 may then flow into afifth return conduit 188, positioned in the second end cap 142, and to asixth body conduit 190. The fluid from the sixth body conduit 190 maythen flow into a sixth return conduit 192, positioned in the first endcap 140, and to a seventh body conduit 194. Air and gases may passthrough the port 166 positioned in the second end cap 142. However,liquids and exudate will be trapped within the canister 110. As usedherein, “fluids” may include liquids, exudate, air, and other gases.

Referring now primarily to FIGS. 7-11, another illustrative embodimentof a canister 210 for use in a reduced-pressure treatment system such asthe system 100 of FIG. 1 is presented. The canister 210 is similar tothe canister 110 shown in FIGS. 1-6 except (i) the canister 210 includesthree fluidly isolated body conduits 248 and (ii) a first end cap 240and a second end cap 242 include protrusions 241, 243, respectively. Thecanister 210 may be used for tissue sites that produce low volumeexudates.

The canister 210 is positioned between the first and second conduits112, 114 of FIG. 1. The canister 210 includes a center body 238, thefirst end cap 240, and the second end cap 242. The canister 210 isconfigured to create a continuous, tortuous flow path represented byarrows 257. The continuous, tortuous flow path is a unidirectional flowpath.

The center body 238 includes a first end 244 and a second, opposing end246. The number of fluidly separate body conduits 248 extend from thefirst end 244 to the second end 246. As shown, the number of fluidlyseparate body conduits 248 is three. The center body 238 may include anabsorbent material (not shown) positioned within one or more of thenumber of fluidly separate body conduits 248. The absorbent material maybe one of a hydrophilic foam, a hydrophilic paper or a hydrophilicpowder.

The first end cap 240 is connected to the first end 244 of the centerbody 238. The first end cap 240 may be connected to the center body 238by a connecting means such as an adhesive bond or a weld bond. The firstend cap 240 may be formed as a single piece and may further be formed ofsilicone.

The first end cap 240 has a return conduit 258 configured to fluidlyconnect one of the body conduits 248 with another of the body conduits248. In one embodiment, the return conduit 258 connects two of thenumber of body conduits 248 that are adjacent. The return conduit 258may function as a turnabout that redirects fluid received from oneconduit into another conduit. The return conduit 258 may redirect fluidinto an opposite direction. The first end cap 240 may include a numberof protrusions 241 corresponding to the return conduit 258. The numberof protrusions 241 are configured to be inserted into the correspondingbody conduits 248.

The first end cap 240 has a port 260 for receiving an inlet conduit,such as the first conduit 112, that is in fluid communication with thetissue site 102. The port 260 is aligned with a first body conduit 262of the number of body conduits 248 to facilitate fluid communicationbetween the first conduit 112 and the first body conduit 262 of thenumber of body conduits 248.

The second end cap 242 is connected to the second end 246 of the centerbody 238. The second end cap 242 may be connected to the center body 238by a connecting means such as an adhesive bond or a weld bond. Thesecond end cap 242 may be formed as a single piece and may further beformed of silicone.

The second end cap 242 has a return conduit 264 configured to fluidlyconnect one of the body conduits 248 with another of the body conduits248. In one embodiment, the return conduit 264 connects two of thenumber of body conduits 248 that are adjacent. The return conduit 264may function as a turnabout that redirects fluid received from oneconduit into another conduit. The return conduit 264 may redirect fluidinto an opposite direction. The second end cap 242 may include a numberof protrusions 243 corresponding to the return conduit 264. The numberof protrusions 243 are configured to be inserted into the correspondingbody conduits 248.

The second end cap 242 has a port 266 for receiving an outlet conduit,such as the second conduit 114, that is in fluid communication with thereduced-pressure treatment unit 108 and, in particular, thereduced-pressure source 134 of FIG. 1. The port 266 is aligned with anend conduit 268 of the number of body conduits 248 to facilitate fluidcommunication between the second conduit 114 and the end conduit 268 ofthe number of body conduits 248. A hydrophobic filter (not shown) may beplaced in the second end cap 242, adjacent the port 266, to preventexudates from exiting the canister 210.

Referring now primarily to FIGS. 12A and 12B, another illustrativeembodiment of a canister 310 for use in a reduced-pressure treatmentsystem such as the system 100 of FIG. 1 is presented. The canister 310may be referred to as an in-line canister since the canister 310 isconnected to the first and second conduits 112, 114 shown in FIG. 1 thatfluidly connect the reduced-pressure dressing 106 and thereduced-pressure treatment unit 108. The canister 310 includes a centerbody 338, a first end cap 340, and a second end cap 342. The canister310 has a cylindrical shape. The canister 310 is configured to create acontinuous, tortuous flow path. The continuous, tortuous flow path is aunidirectional flow path.

The center body 338 includes a first end 344 and a second, opposing end346. A number of fluidly separate body conduits 348 extend from thefirst end 344 to the second end 346. The number of fluidly separate bodyconduits 348 may be an even or an uneven number. For example, the numberof body conduits may be 8. The number may depend on the desired lengthof the continuous, tortuous flow path. The center body 338 may have adiameter, D, of approximately 1-2 inches in some embodiments. In moreparticular embodiments, the diameter D may be approximately 1.6 inches.The center body 338 may also have a length, L, between the first end andthe second end 344, 346 of several inches in some embodiments, andapproximately 4 inches in more particular embodiments. Each of thenumber of fluidly separate body conduits 348 may have a diameter, d, ora width of which allow for an approximate volumetric size of 130 cc. Itshould be understood however, the diameter, D, and length, L, of thecenter body 338, the number of body conduits 348 contained within thecenter body 338, and the diameter, d, or width of the body conduits 348may be adjusted according to the desired volumetric size of the canister310.

The center body 338 is shown as having a cylindrical shape. The centerbody 338 includes an outer surface 351. The outer surface 351 of thecenter body 338 may include a groove 353 that extends along thelongitudinal axis, or the length, L, of the center body 338. The groove353 may be used during the manufacturing process to properly align thenumber of fluidly separate body conduits 348 within the center body 338.The number of fluidly separate body conduits 348 may include a centerconduit 339 and a number of outer body conduits 337 that are radiallypositioned around the center conduit 339. The center body 338 may be asingle extruded piece and may be formed of silicone.

The center body 338 may include an absorbent material (not shown)positioned within one or more of the number of fluidly separate bodyconduits 348. The absorbent material may be one of a hydrophilic foam, ahydrophilic paper or a hydrophilic powder.

The canister 310 further includes the first end cap 340. The first endcap 340 is connected to the first end 344 of the center body 338. Thefirst end cap 340 may be connected to the center body 338 by aconnecting means such as an adhesive bond or a weld bond. The connectingmeans creates a fluid seal between the first end cap 340 and the centerbody 338. The first end cap 340 may be formed as a single piece. Thefirst end cap 340 may further be formed of silicone.

The first end cap 340 includes a first plenum 355 for receiving fluids.The first plenum 355 may have a number of return conduits 358 positionedwithin the first plenum 355. The return conduits 358 are configured tofluidly connect one of the body conduits 348 with another of the bodyconduits 348. The return conduits 358 may function as turnabouts thatredirect fluid received from one conduit into another conduit. Thereturn conduits 358 may redirect fluid into an opposite direction. Thefirst end cap 340 may include a number of protrusions 341 correspondingto the return conduits 358. The number of protrusions 341 are configuredto be insertable into the corresponding body conduits 348.

The first end cap 340 has an inlet port 360 for receiving an inletconduit, such as the first conduit 112, and an outlet port 366 forreceiving an outlet conduit, such as the second conduit 114. The inletconduit, or the first conduit 112, is in fluid communication with thetissue site 102, and the outlet conduit, or the second conduit 114, isin fluid communication with the reduced-pressure source 134. The firstconduit 112 may be connected to the inlet port 360 and the secondconduit 114 may be connected to the outlet port 366 by a connectingmeans such as an adhesive bond or a weld bond. The connecting meanscreates a fluid seal between the first conduit 112 and the inlet port360 and the second conduit 114 and the outlet port 366. The inlet port360 is aligned with one of the number of body conduits 348. In oneembodiment, the inlet port 360 is aligned with one of the number ofouter body conduits 337 such as a first body conduit 362. In anotherembodiment, the inlet port is aligned with the center conduit 339. Theinlet port 360 aligns with one of the number of body conduits 348 tofacilitate fluid communication between the first conduit 112 and the oneof the number of body conduits 348. The inlet port 360 may include aprotrusion 359 for inserting into the one of the number of body conduits348. The outlet port 366 is aligned with another of the number of bodyconduits 348. In one embodiment, the outlet port 366 is aligned with thecenter conduit 339. In another embodiment, the outlet port 366 isaligned with one of the radial body conduits such as the first bodyconduit 362. The outlet port 366 aligns with another of the number ofbody conduits 348 to facilitate fluid communication between the secondconduit 114 and the another of the number of body conduits 348. Ahydrophobic filter (not shown) may be placed in the first end cap 340,adjacent the outlet port 366, to prevent exudates from exiting thecanister 310.

The canister 310 further includes the second end cap 342. The second endcap 342 is connected to the second end 346 of the center body 338. Thesecond end cap 342 may be connected to the center body 338 by aconnecting means such as an adhesive bond or a weld bond. The connectingmeans creates a fluid seal between the second end cap 342 and the centerbody 338. The second end cap 342 may be formed as a single piece. Thesecond end cap 342 may further be formed of silicone.

The second end cap 342 includes a second plenum 357 for receivingfluids. The second end cap 342 has a number of return conduits 364positioned within the second plenum 357. The return conduits 364 areconfigured to fluidly connect one of the body conduits 348 with anotherof the body conduits 348. The return conduits 364 may function asturnabouts that redirect fluid received from one body conduit intoanother body conduit. The return conduits 364 may redirect fluid into anopposite direction. The second end cap 342 may include a number ofprotrusions 343 corresponding to the return conduits 364. The number ofprotrusions would be insertable into the corresponding body conduits348.

In operation, reduced pressure is supplied to the tissue site 102 by thereduced-pressure treatment unit 108. The canister 310 is a part of thesystem 100 that communicates the reduced pressure from thereduced-pressure treatment unit 108 to the tissue site 102. Whileapplying reduced pressure to the tissue site 102, fluids, includingliquids and exudates, may be removed from the tissue site 102. Theliquids and exudates removed from the tissue site 102 are collected andstored in the canister 310. The fluid connection between the bodyconduits 348 and the return conduits 358, 364 of the first and secondend caps creates a continuous, tortuous flow path. The continuous,tortuous flow path is a unidirectional flow path beginning at the inletport 360 in the first end cap 340 and ending at the outlet port 366 inthe first end cap 340. The continuous, tortuous flow path passes throughthe each of the number of fluidly separate body conduits 348.

In one illustrative, non-limiting embodiment, the fluids removed fromthe tissue site 102 enter the canister 310 through the inlet port 360 inthe first end cap 340. The fluids are delivered through the inlet port360 and into a first body conduit 362 of the number of body conduits348. The fluids may then flow through the first body conduit 362 to afirst return conduit 372, positioned in the second end cap 342, into asecond body conduit 374. The fluid from the second body conduit 374 maythen flow into a second return conduit 376, positioned in the first endcap 340, to a third body conduit 378. The fluid from the third bodyconduit 378 may then flow into a third return conduit 380, positioned inthe second end cap 342, to a fourth body conduit 382. The fluid from thefourth body conduit 382 may then flow into a fourth return conduit 384,positioned in the first end cap 340, to a fifth body conduit 386. Thefluid from the fifth body conduit 386 may then flow into a fifth returnconduit 388, positioned in the second end cap 342, to a sixth bodyconduit 390. The fluid from the sixth body conduit 390 may then flowinto a sixth return conduit 392, positioned in the first end cap 340, toa seventh body conduit 394. The fluid from the seventh body conduit 394may then flow into a seventh return conduit or end conduit 396positioned in the second end cap 342, to the center conduit 339. Air andgases may pass through the outlet port 366 positioned in the first endcap 340. However, liquids and exudate will be trapped within thecanister 310. In this embodiment, fluid received by the inlet port 360travels through each of the outer body conduits 337 prior to reachingthe center conduit 339 and traveling towards the outlet port 366.

Referring now primarily to FIGS. 13A and 13B, another illustrativeembodiment of a canister 410 for use in a reduced-pressure treatmentsystem such as the system 100 of FIG. 1 is presented. The canister 410is similar to the canister 310 shown in FIGS. 12A and 12B except a firstand second end cap 440, 442 do not include return conduits.

The canister 410 includes a center body 438, a first end cap 440, and asecond end cap 442. The canister 410 has a cylindrical shape and isconfigured to create a tortuous flow path. The center body 438 includesa first end 444 and a second, opposing end 446. A number of fluidlyseparate body conduits 448 extend from the first end 444 to the secondend 446. The center body 438 includes an outer surface 451. The outersurface 451 of the center body 438 may include a groove 453 that extendsalong the longitudinal axis, or the length of the center body 438. Thenumber of fluidly separate body conduits 448 may include a center bodyconduit 439 and a number of outer body conduits 437 that are radiallypositioned around the center body conduit 439. The center body 438 maybe a single extruded piece and may be formed of silicone.

The center body 438 may include an absorbent material (not shown)positioned within one or more of the number of fluidly separate bodyconduits 448. The absorbent material may be one of a hydrophilic foam, ahydrophilic paper or a hydrophilic powder.

The canister 410 further includes the first end cap 440. The first endcap 440 is connected to the first end 444 of the center body 438. Thefirst end cap 440 may be connected to the center body 438 by aconnecting means such as an adhesive bond or a weld bond. The first endcap 440 may be formed as a single piece and may further be formed ofsilicone.

The first end cap 440 includes a first plenum 455 for receiving fluids.The first end cap 440 has an inlet port 460 for receiving an inletconduit, such as the first conduit 112, and an outlet port 466 forreceiving an outlet conduit, such as the second conduit 114. The inletconduit, or the first conduit 112, is in fluid communication with thetissue site 102, and the outlet conduit, or the second conduit 114, isin fluid communication with the reduced-pressure source 134. The firstconduit 112 may be connected to the inlet port 460 and the secondconduit 114 may be connected to the outlet port 466 by a connectingmeans such as an adhesive bond or a weld bond. In one embodiment, theinlet port 460 is in fluid communication with all but one of the numberof body conduits 448. For example, the inlet port 460 may be in fluidcommunication with the outer body conduits 437. In this example, theoutlet port 466 is in fluid communication with the center body conduit439. The outlet port 466 may include a protrusion configured to bepositioned within the center body conduit 439. The first plenum 455 isan open space or cavity. Fluids received by the inlet port 460 enter thefirst plenum 455 and are distributed to the outer body conduits 437. Thefluids pass through the outer body conduits 437 and enter the second endcap 442 having a second plenum 457.

The second end cap 442 is connected to the second end 446 of the centerbody 438. The second end cap 442 may be connected to the center body 438by a connecting means such as an adhesive bond or a weld bond. Thesecond end cap 442 may be formed as a single piece and may further beformed of silicone. The second end cap 442 includes the second plenum457 for receiving fluids. The second plenum 457 is an open space orcavity that receives fluids from one or more of the number of bodyconduits 448 in fluid communication with the inlet port 460 such as theouter body conduits 437. Fluid received by the second plenum 457 isdirected into the center body conduit 439 and to the outlet port 466.Fluid in the second plenum 457 may be directed into the center bodyconduit 439 by means of reduced pressure.

In another embodiment (not shown), the inlet port 460 is fluidlyconnected with one of the number of body conduits 448. The inlet port460 aligns with one of the number of body conduits 448 to facilitatefluid communication between the first conduit 112 and the one of thenumber of body conduits 448. The inlet port 460 may include a protrusionfor inserting into the one of the number of body conduits 448. Theoutlet port 466 is aligned with the other conduits of the number of bodyconduits 448.

In operation, reduced pressure is supplied to the tissue site 102 by thereduced-pressure treatment unit 108. The canister 410 is a part of thesystem 100 that communicates the reduced pressure from thereduced-pressure treatment unit 108 to the tissue site 102. Whileapplying reduced pressure to the tissue site 102, fluids, includingliquids and exudates, may be removed from the tissue site 102. Theliquids and exudates removed from the tissue site 102 are collected andstored in the canister 410. The fluid connection between the bodyconduits 448 and the first and second end caps 440, 442 creates atortuous flow path having several parallel paths. The tortuous flow pathbegins at the inlet port 460 in the first end cap 440 and ends at theoutlet port 466 in the first end cap 440. The tortuous flow path passesthrough each of the number of body conduits 448.

In one illustrative, non-limiting embodiment, the fluids removed fromthe tissue site 102 enter the canister 410 through the inlet port 460 inthe first end cap 440. The fluids are delivered through the inlet port460 into the first plenum 455. The fluid is then directed to any one ofthe outer body conduits 437. The fluid is received by the second plenum457 and directed into the center body conduit 439.

It should be apparent from the foregoing that an invention havingsignificant advantages has been provided. While the invention is shownin only a few of its forms, it is not just limited but is susceptible tovarious changes and modifications without departing from the spiritthereof.

We claim:
 1. A canister for use in administering reduced pressure to atissue site, comprising: a fluid input for fluid connection to a reducedpressure dressing; a fluid output for fluid connection to a source ofreduced pressure; a plurality of conduits extending within the canister;a first plenum having an inlet port forming the fluid input and in fluidcommunication with a first end of a first subset of the conduits; and asecond plenum in fluid communication with a second end of a secondsubset of the conduits; wherein the fluid input is fluidly connected tothe fluid output by a continuous tortuous flow path, wherein the fluidoutput is in fluid communication with the first end of the subset of theconduits, and wherein the first and second subsets of conduits arediscrete from each other.
 2. The canister of claim 1, wherein thecontinuous tortuous flow path is formed of a lumen within the canister.3. The canister of claim 1, wherein the continuous tortuous flow pathcomprises a plurality of sections of lumen arranged in parallel in abody part of the canister.
 4. The canister of claim 1, wherein thecanister further comprises: a center body having a first end, a secondend, and comprising the plurality of conduits; a first end cap connectedto the first end of the center body, the first end cap comprising thefirst plenum, the inlet port, and an outlet port; and a second end capconnected to the second end of the center body, the second end capcomprising the second plenum.
 5. The canister of claim 1, wherein thecontinuous tortuous flow path is formed of a plurality of conduitsarranged in parallel in a linear arrangement.
 6. The canister of claim1, wherein the flow path is formed of a plurality of conduits fluidlyconnected by conduits having a 180° bend.
 7. The canister of claim 1,further comprising an absorbent material positioned within the flowpath.
 8. The canister of claim 7, wherein the absorbent material is oneof a hydrophilic foam, a hydrophilic paper, or a hydrophilic powder.